Power interlocking system for railroads



Se t. 22, 1931. F. BENEDICT POWER INTERLOCKING SYSTEM FOR RAILROADS Filed July 9, 1929 7, mvsgmg BY I 1/ a ATTORNEY Patented Sept. 22, 1931 umrizna STATES PAT T" OF F1 CE- FRANK BENEDICTaOE, RUTHERFORD, NEW JERSEY ASSIGNOR TO GENERAL RAILWAY SIGNAL COMPANY, OF ROCHESTER, NEW YORK POWER INTERLOCKI'NG, SYSTEM' FOR RAILROADS Application filed' July 9, 1929. Serial No. 377,034.

This invention relates to power interlocking systems for rallroads, and more 'particularly to means forrsafeguanding the operation of power operated switches, especially 'when it"isinecessary to operatelthem by hand,

or under emergency conditions.

heir itbecomes necessary to I operate a switch machine by hand, it isdesirable that suitableprovision he made'toiinsure care and due responsibility in placing said switch; ma-

chine back under normal powencontrol; In one type of switch machine, to which the present invention is the specific form shown and described is particularly" applicable, before ""the hand crank for operating the machine manually can-be used, power must be cut off from the switch machine, special contacts. being provided for'this purpose. 3 .Itsometimes happens that these contacts are" closed accidentally or carelessly afterthehand crankinghas been completed, at a timeand under such conditions that a l-improper power operation of'theswitch may'occur; and one object of the present inventionis to provide ineansfor safeguarding the restoration of the switch machine to norma-lpower operation.

In the practical operationlof power-' interlocking systems, it sometimes becomes expedicut or necessary to operate a switch under special'or emergency conditions, an emergencv release device being commonlyused for this purpose; Another object of this invention is to provide ail-improved type of emergency release device, which must bespecially manipulated in order cooperate a switch, so as to avoidcareless or accidentalmisuse.

The characteristic features of the invention. and its advantages,will be in part apparent and in-part' pointed out'as the descrip- 'tion progresses. f

Theaccompanying-drawing shows in a d1 agrannnatic and conventional manner one specific'embodiment of'theinvention;

' While the invention will take various i orms, depending upon the type o'f interlocking system and conditions encountered in practice, an explanationiof theinvention, :as .7

applied to anelectric'interlocking systenr of the wellfknown dynannc'indication type. Wlll make clear the features and; functions ofathe skilled in the art, characteristic of this particular dynamic indication type of system, as more fully explained, for example, in the patent to Howe, No. 1,550,611, August 18, 1925. For thepurposes of this invention, the electric lock L is preferably of the force-dro type, effective in the normal and reverse indication positions of the lever, as disclosed, for example,in the patent to Carter et al., No. 1,566,901, December 22, 1925.

Associated with the leverLV, and located in the tower, is a power control relay LR, which controls the supply of operating current to the contacts of the lever from the battery B, or other suitable source of current, over wire 6, through the-front contacts 7 of the relay LR, arranged in multiple, wire 8 and fuse 9 to the safety magnet- S. This relay LR is of any suitable construction capable of breaking switch machine operating current and is operable either on direct our- 7 rent or alternating current, depending upon the source'of energy used; and when this relay'LR is de-energized, power is cut off from the contacts controlled by the lever LV, and theswitch machine controlled thereby can not be operated. I

Also associated with the lever LV, and preferably located in the tower, is a relay P, conveniently called a protective relay, and a reset button RS. This protective relay P is of any suitable constructiomand' is provided with two front contacts and 11. The reset button RS, shown diagrammatically comprises a manually operable contact member 1-2, movable from anormal position as shown. out of engagement with cooperating contacts, indicated conventionally as arrows, into engagement with another pair of cooperating contacts.

In the tower is also an emergency release device ER, preferably of the screw release different longitudinal positions of this spindle. By turning the crank 15 the operator may move the spindle 14 back and forth to close and open circuits through these contact members 18, 19 and 20. This emergency release device has three different positions, one a normal position as shown, in-

dicated by the dotted line 0, another position toward the left from the normal position indicated b T the dotted line 1 in which a 7 1 the contactmemoer 18 only compietes a cir- 'cuit through its cooperating contacts; and a third position, indicated by the dotted line 2, in which the contact member 18 only completes a circuit through another cooperating pair of contacts.

The control lever LV serves to control the application of operating current over normal and reverse operating wires N and R and a common wire C, to a suitably electrically operated switch machine SM, connected to the points of the switch SW This switch machine SM, shown conventionally, is preferably of the construction shown and described in the patent to Howe, To. 1,466,903, September 4, 1923. Associated with the switch SWV is the usual signal'21,

governing trafiic over this switch, and the usual detector track circuit, comprising a track iattery 22, or other source of current, and a track relay T, having a front contact 23.

The switch machine SM, as shown and described more in detail in said Howe Patent, No. 1,466,903, includes means for permitting its hand operation. This means includes a soclret (indicated at 24 in the drawing) adapted to receive the end of a hand crank (not shown), so that by turning the crank, the gearing of the switch machine may be op rated by hand to unlock and operate the switch. This socket 24 for the hand crank is normally obstructed or partly covered by a guard plate 25, pivoted at 26, so arranged that the hand crank can not 1 be inserted, until. this guard plate is pushed aside to align an opening 25 therein with the socket 24. The guard plate 25 is con nected to a rod 27, carrying an lnsulated contact member 28 whichnormallycompletes a ,7

be thus stopped in IIllCl-St-IOkQ; but this con circuit througha pairof cooperating. contact springs 29. JJhen the guard plate 25 1s shifted to permit hand cranking of the switch machine. the circuit through the contact 23 and the contact springs 29 is broken.

The parts are shown 1n the drawlng 1n the normal condition. The various circuits involved are shown for simplicity as terminating at the symbols and indicating the opposite terminals of a battery, or other suitable source of direct or alternating current.

The protective relay P is normally energized by a stick circuit which may be traced from through the contact fingers 29 and contact 28 of the guard plate 25, wire 30, front contact 10 of relay P, wires 31 and 32, relayPto(-). v The power control relay LR is normally energized by a circuit which may be traced from through the front contact 23 of the track relay T, wire 33, front contact 11 of'relay P, wire 34, reset contact 12 and its normally closed contacts 35, Wire 36, relay LR to The electric lever look, upon actuation of the latch contacts 5, may be energized by a circuit from through the front contacts 23 of the track relay T, wires 33, 37 and 38, contact 19 of the emergency release ER, wires 39and 40, latch'contacts 5, wire 41, magnet of electric lock L, to,

ith the parts in this normal condition,

'if there is no train on the detector track circuit and the track relay T is energized, the electric lever lock L may be energized, so that the lever LV may be moved to the reverse position; and since the relay LR is also energized, power may be applied to the switch machine to operate it to the reverse POSIUOH, and cause it to generate dynamic indication current, all in the way characteristic of this type of system, which need not be explained in detail. If, however, the detector track circuit is occupied, the electric lever lock L can not be energized, and therelay LR is also de-energized, so that power can not be applied to the switch machine.

in order that the operator may know when normal operation is possible, a lever lamp is preferably employed, energized over a .cir-

cuit from through the front contact 23 of the track relay T, wires 33, 37 and 38, contact 19 of emergency release device ER, Wires 39, 40, and 51, front contact 52 of relay LR, wire 53, lamp 50, to

If, for any reason, after the lever LV has been operated, while the detector track circuit was unoccupied, a train should enter this detector-track circuit while the switch machine is operating, the dropping of the track Jrelay T; and the power control relay LR at once cuts off the supply of power to the switch machine and stops its operation. Under certain conditions, the switch machine might dit'ion is considered to be preferable, particularly for subways; but if desired, arrangements may be made, such as disclosed in the Howe Patent, No. 1,550,611, above mentioned, so that the switch machine will complete a cycl'e'of operation once started before the detectortrack circuit becomes occupied. i

Assume now that it becomes necessary,.for

some reason, to operate the switch machine shifted to open contacts'28and 29, andthis breaks the sticlccircuit'for the relay P; which in turn, being tie-energized, opens its front contact 121 and tie-energizes the relay LR,

thereby cuttingiofi the: supply of power to the switch machine The protective relay P, once d'e-energizedin this Way, remains deenergized, even a fter the handcranking is completed and the: guardplate 25 is restored tothe normal position to close the contacts 28- and 29; and beforepower can again be applied to the switch: m'acl1ine, the reset button RS must be operated: to: close the pick-up circuit for the relay P, which maybe traced from )3, through the contact 12. of the reset button RS and its normally open contacts;-l2;lwires43. and 32,.relay P to Thus, after the switch machine has been cranked by hand, and the guard: plate 25 has been: restored, the reset button RS'must be specially manipulated before power is: restored to the switch machine. This reset butt'oirispreferably located in the towei, and may be actuated by the operator upon instruction from the maintainer at the switch, it so desiredg ortthe key to obtain access to the'reset button RS maybe held: only by the maintainer, so:that; he is required to return to the towerfiand operate this reset button after having cranked the switch machine by hand. Also, if so 'desirechthe reset button RS maybe located in a-suitably sealed or locked boxadjacent to the; switch; The object of the invention is to require special manipulation to restore power to a switch machine that has been hand operatedrand the reset button RS may be located or safe,- guarded in any suitable way to accomplish this purpose. i

\Vhen the reset button BS is operated to energize the relay P; the" normally closed contacts 12-35 of: this reset button are opened; so that the relay LR remains deenergized, even though the. relay 1 1s restored Consequently, the reset-button RS must be returned to: the normal position to 1'. come necessary to operate the switch by of the lQVGI'lOCk L. Under these conditions,

power in the regular way; even though the track? relay T, or other approach or look ing relays: governing the :energization of" the lever lock L and the lock control relay LR, are (lo-energized, and actto prevent. the normal' power operation of the switch; For this purpose, the emergency release device-ER is provided.

To understand: the functions and operation of this emergency release device ER,=assu1ne that the detector track circuit has failed for some reason, and that the fnontcontact23 of thetrack relay T is open. This de-energizes the relay LR, and prevents theenergization after taking suitable precautionsto be sure thatit is safe to opcrate the switch, the operator by turning the crank 15 may move the spindle 14 tothe left from the normal: position shown to the first operated. position, indicated bythe-dotted line 1, thereby closing acircuit for energizing the: electric lock L which maybe traced from. wires 44 and 45, contact 18WVlreS wand 40, latch contact 5, wire ilg electric lock Lrto This permits theoperat'or to movethe lever LV tothe other indication position, establishing at the lever contacts the next operating circuit. for the switch machine, but since the relay'LRis still de-energizedunder the'conditionsassumed, no

operation of the switchmachine occurs. The

operator, after moving the lever LV, must bring the spindlele' into the second operated position by turning the crank 1 5v furtheigindicated by the dotted line 2; thereby establishing a circuit for energizing-therelay LR, which maybe traced as follows :-fronr Wires and 47,-contact 1S,1Wires- 4 8 and 37, front contact 11 of the relay P, (which isassumed to be energized), V and thence through the relayLR the'same as in the normal energizing circuit for that relay. This permits the application: of power to the switch machine; but'befbre the signal 21, governing tnafiih' over the switch can be cleared, the

emergency release device must be cranked backl to'its initial'or normal position shown to close fi/CIICUll? through its contact 20, the completecont'rol GllCllltS for the signalnot been-shown ,rsincethey will take the usual form well known: in the art-.-

It shouldzbenotedthat the lever lock L and the power control relay LR. are energized in diii'erent positions of the emergency. release device ERL Consequently, for safe opera- .tion of the switcln whilet'he. detector track relay T; or equivalent route or approach locking relays (not sliown),'are de-energized, the operator must manipulate'the emergency release device, first to a position to release the lever, and then move'the'lever, and then opmate the emergeneyjrelease device again to a positionto' energize therelayLR andapply power to the 'switchniachine; Thus the emergency releasevdevice EH can notvbe carelessly or accidentally left in a position where the switch machine can be operated by power .independent of the normal safeguards for such power operation; but for each such emergency operation of the switch machine, the operator must make a special manipulation, so that he is required to take suitable precautions, in accordance with the rules, for each power manipulation of the switch under such emergency conditions.

The particular construction and arrangement of parts and circuits shown and described is merely typical or representative of one specific embodiment of the invention; and it should be understood that the invention is applicable to various types of power interlocking, and is susceptible of considerable modification and adaptation to fit clifferent conditions encountered in practice.

hat I claim is 1. In a power interlocking system, a switch machine, means permitting hand operation of the switch machine and including a manually movable member whichmust be shifted before this machine can be operated by hand, electrically operable power control means for cutting oil the supply of power to said switch machine controlled electrically and rendered effective by the movement of said member, said power. control means when once operated remaining in that condition until specially restored, and manually. operable means for restoring said power control means.

2. In a power interlocking system, a switch machine, means when in a changed condition permitting manual operation of said switch machine, means including a normally energized stick relay governed bysaid first'mentioned means for controlling the application of power to the switch machine, and a manually controlled pick-up circuit for said stick relay.

3. In a power locking system, a switch machine having'contacts opened to permit hand operation thereof, a normally energized stick relay acting when de-energized to interrupt the supply of power to said'switchmachine, a stick circuit for said relay including said contacts, a manually operable reset circuit controller, and a pick-up circuit for said relay including said circuit controller.

, at. In a power interlocking system, a switch 'machine having contactsopened when it is operated by hand, adetector track circuit, a stick relay having its stick circuit broken by "the. openingof said contact, a power control device forcutting ofi' the supply of power to .said switchxmachine, said device being actuated by said stick relay when de-energized and.by said detector track circuit when occupied, and a manually operable circuit con troller movable to establish a pick-up circuit for said stick relay, said circuit controller wheninits moved position rendering said power control device effective to cut oil the supply of power to the switch machine.

5. In a power interlocking system, a switch machine and a control lever therefor, a detector track circuit, a lock for said lever controlled by said track circuit, a power control device for governing the supply of power to said lever also controlled by said track circuit, and an emergency release device effective in one position to render said lever lock ineffective independently of its control by said track circuit, andin another position to govern said power control device to supply power to the switch machine independently of the control of said track circuit.

6. In a power interlocking system, a switch machine, a control lever, a lever l0ck,a power control device, a detector track circuit governing both said lock and said power control device, and an'emergency release device effective in different positions to actuate said lock and power control device independently of their control by said track circuit.-

7. In a power interlocking system, a control lever, a lever lock, a power control relay, a detector track circuit controlling both said lever lock and said power control relay, circuits for energizing said lock and said power control relay independently of their control by said detector track circuit, and a manually operable release device efiective in different positions to close said circuits.

8. In an interlocking system, a control lever, an electric lever lock, a power cutofi' device, means for rendering said lever lock;

and power cut-off device effective, and other manually operable means for rendering said lock and power cut-off device ineffective separately and independently and in different conditions of said means.

.9. In a safety system for power-operated switches, a switch machine, a control lever in a tower at'a point distant from said switch machine for governing the operation thereof, means permitting hand operation of the switch-machine and including a manually movable member which must be shifted to an abnormal position before the switch can be operated by hand, an electrically operable power control device in the tower controlling the supply of current to said control lever, said device being actuated by the movement of said member to its abnormal position to cut off the supply of power to said switch machine, said device when changed to its abnormal condition remaining in that condition until specially restored, and manually operable restoring means in the tower for restoring said power control. device to normal, said restoring means when in its restoring position acting independently of said device to prevent the application of power to the switch machine.

10 In a safety system for power-operated switches, the combination with a power-operated switch machine, a control lever, a detector track circuit adjacent the switch, said switch machine having an opening adapted to receive a hand crank for operating the switch machine by hand, a manually movable member adapted to obstruct said opening and which must be shifted before said hand crank can be inserted in said opening, and an electrically operable power control device con trolled jointly by said detector track circuit and by said manually movable member for cutting ofl the supply of current to the contacts of said control lever if said track circuit is occupied or said manually movable member is in its shifted position.

11. A system for protecting power-operated switch machines comprising, a switch machine having a crank socket for permitting hand operation, a movable guard plate normally obstructing said socket, contacts opened by movement of said guard plate to give access to the crank socket, a normally energized stick relay acting when deenergized to prevent operation of said switch machine, a

stick circuit for said relay including said contacts, a manually operable reset circuit controller movable to a restoring position to establish a pick-up circuit for said stick relay, and means associated with said circuit controller for independently preventing operation of the switch machine while said circuit controller is in its restoring position.

12. In a system for protecting the operation of power switch machines, a control lever, an electrically operable lever lock for preventing movement of said lever to its controlling positions, a power control device governing the supply of current to the contacts of said control lever, a detector track circuit, normal energizing circuits for said lever lock and said power control device both simultaneously controlled by said detector track circuit, release'circuits for energizing said lever lock and said power control device independently of said detector track circuit, and an emergency screw release effective in diiferent positions to close said release circuits separately.

13. In a system of the type described, a switch machine provided with means for permitting its hand operation and having crank contacts which must be opened before said switch machine can be operated by hand, a control lever for governing the operation of said switch machine, a detector track relay, a normally energized stick relay having a stick circuit including said crank contacts, a power control relay governing the supply of current to the contacts of the control lever, an energizing circuit for said power control relay including a front contact of said stick relay and a front contact of said detectortrack relay, and a manually operable reset circuit controller having normally closed contacts and normally open contacts, said normally closed contacts of said circuit controller being included in said energizing circuit for the power control relay, said normally open contacts of said circuit controller being included in a pick-up circuit for said stick relay.

14. In a system of the type described, the combination with a power-operated switch machine and a control lever therefor, of an electric lock for said lever, a power control relay governing the supply of current to the contacts of said lever, an emergency screw release device having normally closed contacts and two normally open contacts, said contacts all being closed in different positions of said release device, an energizing circuit for said electric lock including said normally closed contacts, and other energizing circuits for said electric lock and said power control relay respectively including the normally open contacts of said screw release device.

In testimony whereof I aifix my signature.

FRANK BENEDICT.

DI so A| M E R 1,824,113.F1"anlc Benedict, Rutherford, N. J. POWER INTERLOCKING SYSTEM FOR RAILROADS. Patent dated September 22, 1931. Disclaimer filed February 16, 1934, by the assignee, General Railway Signal Company.

Hereby enters this disclaimer to claims 1, 2, 3, and 4 of said Letters Patent, which are in the following words, to wit:

. 1. In a power interlocking system, a switch machine, means permitting hand operation of the switch machine and including a manually movable member which must be shifted before this machine can be operated by hand, electrically operable power control means for cutting off the supply of power to said switch machine controlled electrically and rendered effective by the movement of said member, said power control means when once operated remaining in that condition until specially restored, and manually operable means for restoring said power control means.

2. In a power interlocking system, a switch machine means when in a changed condition permitting manual operation of said switch machine, means including a normally energized stick relay governed by said first mentioned means for controlling the application of power to the switch machine and a manually controlled pick-up circuit for said stick relay. i

3. In a power locking system, a switch machine having contacts opened to permit hand operation thereof, a normally energized stick relay acting when de-energized to interrupt the supply of power to said switch machine, a stick circuit for said relay including said contacts, a manually operable reset circuit controller, and a pick-up circuit for said relay including said circuit controller.

4. In a power interlocking system, a switch machine having contacts opened when it is operated by hand, a detector track circuit, a stick relay having its stick circuit broken by the opening of said contact, a power control device for cutting off the supply of power to said switch machine, said device being actuated by said stick relay when de-energized and by said detector track circuit when occupied, and a manually operable circuit controller movable to establish a pick-up circuit for said stick relay, said circuit controller when in its moved position rendering said power control device effective to out off the supply of power to the switch machine.

[Ofiicial Gazette lVIarch 18, 1.984.] 

